Impact of Six Months of Various Modalities of Exercise on Stress in Post-Treatment Breast

Impact of Six Months of Various Modalities of Exercise on Stress in Post-Treatment Breast Cancer Survivors

Terri Boggess, PhD1, Daniel C. Hughes, PhD2, Lorenzo Cohen, PhD3, Nydia Darby, DPT4, Amelie G. Ramirez, DrPH2

1. St. Mary’s University – Exercise & Sports Science Department 2. The University of Texas Health Science Center - San Antonio – Institute for Health Promotion Research 3.The University of Texas M. D. Anderson Cancer Center – Integrative Medicine Program 4. Nydia’s Yoga Therapy – San Antonio Texas

Key Words: Stress, Breast Cancer,Yoga

Objective: To study the impact of three modalities of exercise on self-reported and physiological stress markers for post-treatment breast cancer survivors. Methods: Participants were randomized to either a yoga-based exercise program (YE), a “conventional” comprehensive exercise (CE) program (aerobic, resistance, flexibility) or to a group (C) of participants who chose their own form of exercise. All groups were asked to exercise three hours per week. Measures in our model included the Perceived Stress Scale (PSS), salivary cortisol, Medical Outcomes Short-Form- 36 (SF-36) scales, Pittsburg Sleep Quality Index, Family Quality Index, Motivational Profile and Inflammatory Markers. Cortisol samples were collected over five different daily time- points on two consecutive days at the start of the study (pre) and at six month conclusion (post). PSS and SF-36 measures were collected pre and post as well as six months later as a follow-up assessment. All other markers were measured at pre and post except the Motivational Profiles. Results: All cortisol measures improved (slope, area under the curve, mean level) in the expected direction but did not reach statistical significance. PSS improved (p < .001), as did the SF-36’s Mental Component Scale (MCS) (p < .001), Social Functioning (p <.001), and Mental Health (p =.001) subscales. Also improving were Physical Component Scale (PCS) (p < .001) and Physical Functioning (p < .001). These improvements in the self- reported measures continued at the six-month follow-up. There were also improvements in Sleep Quality (sleep latency (p = .032) and improved day functioning from better sleep (p = .008). Conclusion: Incorporating a holistic model, results indicated a favorable impact on self-reported stress and a trend toward improvement in the physiological stress response. However, it is difficult to interpret the clinical impact of the improvements from our results. Our study also suggests that it is the consistent engagement in some form of exercise that has a greater impact on the reduction of stress rather than any one particular modality of exercise. The Yoga protocol used in the study produced results approaching the Comprehensive Exercise group’s results in stress reduction.